This pane contains settings for the optimization during the rendering process. Here you can turn on/off various
flags that try to optimize bounding and buffering to speed up rendering, often at the cost of increased RAM memory
usage.

Early versions of POV-Ray had no automatic bounding to speed up rendering. Users had to manually creating bounding
boxes to speed up rendering. For most scenes using the automatic bounding is faster and you should keep this setting
on, but some old scenes may expect the old bounding mechanism.

Early versions of POV-Ray had no automatic bounding and handled unions a little bit different. Some scene files
expect the old way unions could be used for and will not work with this option activated.